We show a new polarization- and angle-insensitive ultrathin metasurface design using four conjugated hexagonal split-ring resonators (CHSRRs). The CHSRRs are made of copper and arranged in a λ/4 cell-size polyimide film substrate with a dielectric constant of 3.5 and thickness of 0.2 mm (λ/400 at 3.75 GHz). Each CHSRR aperture faces one corner of the square unit cell, thus forming a conjugated loop to achieve TE and TM polarization-insensitive behavior in a wide range of incident angles. Results demonstrated a -10 dB impedance bandwidth of 530 MHz (3.44 to 3.97 GHz) under normal incidence, partially covering the n77 band used for 5G applications.
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